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Glucose isomerase (GI), an enzyme with deserved high potential in the world market. GI plays a major role in high Fructose Corn Syrup Production (HFCS). HFCS is used as a sweetener in food and pharmaceutical industries. Streptomyces are well-known producers of various industrially valuable enzymes, including Glucose isomerase. Currently, recombinant strains have been available for the production of various enzymes, but it has limitation in the large scale production. Therefore, identifying effective streptomyces strains have emerged. The current study, the novel S. lividans RSU26 was isolated from a marine source and optimized its potential to produce glucose isomerase at different physical and chemical conditions. The optimum pH and temperature for GI and biomass production were 7.5 and 35 °C, respectively at 96 h. Characterization study revealed that the approximate molar mass of GI was 43 kDa for monomeric and 170 kDa for tetrameric forms. Kinetic behavior exhibits Km, and Vmax values for the conversion of fructose to glucose conversion were 48.8 mM and 2.54 U mg−1 at 50 °C and glucose to fructose were 29.4 mM and 2.38 U mg−1 at 65 °C protein, respectively. Therefore, the present study suggested that the wild–type S. lividans RSU26 has strong potential to produce glucose isomerase for various industrial applications. Keywords: Streptomyces, Glucose isomerase, Optimization, Purification, Kinetics

A strain of Lysinibacillus, isolated from spoiled fruits and vegetable wastes, was found having an inhibitory effect against foodborne pathogens. Subjected to study of different physico-chemical parameters followed by characterization based on the 16S rRNA gene, it was found exhibiting resemblance to L. boronitolerans (99%), L. xylanilyticus (98%) and L. macroides (97%) respectively. The isolate was annotated as Lysinibacillus JX402121 and found that the production capacity of the specific product recognized as bacteriocin during growth in medium the bacteriocin was further purified to homogeneity by ammonium sulphate precipitation followed by gel filtration chromatography. MALDI-TOF/MS analysis of the substance revealed it to be a 51 kDa bacteriocin, showing greater resemblance with a catalytic bacterial protein, uracil-5-methyl transferase. Based on the physico-chemical characteristics and N-terminal (IKKAPVQKNENYEV) sequence, this novel bacteriocin was found representing a class III bacteriocin. This was found highly active against foodborne bacterial pathogens, Bacillus pumilus (MIC-22 μg/mL), which is responsible for pumilacidins like food toxin. Having great potential against foodborne pathogens, Lysinibacillus JX402121 isolate will be utilized in the production of bacteriocin that acts as a bio-preservative agent against different food-borne pathogens.

The present study was aimed to test cholesterol reduction and vitamin B12 production abilities of the isolated lactic acid bacteria (LAB). Three LAB isolates, namely, Enterococcus faecium (EF), Enterococcus faecium (Chole1), and Lactobacillus pentosus (7MP), having probiotic potential, were isolated from yoghurt. These isolates were screened for bile salt hydrolase (BSH) activity, cholesterol reduction property in MRS broth, and the production of vitamin B12. The present study revealed that the isolate 7MP possesses the highest potential of (48%) cholesterol reduction compared to the other isolates. The isolates EF and Chole1 produced a good amount of (1 ng/mL) vitamin B12. These isolates were identified by 16S rRNA gene sequencing and confirmed by MALD_TOF analysis. Thus, the use of these LAB isolates for yoghurt-making can offer the value addition of lowering cholesterol and vitamin B12 fortification in fermented food.

Expanding applications of metal-oxide nanoparticles (NPs) and increased environmental deposition of NPs followed by their interactions with edible crops threaten yields. This study demonstrates the effects of aging (45 days in soil) of four NPs (ZnO, CuO, Al2O3, TiO2; 3.9–34 nm) and their corresponding metal oxide bulk particles (BPs; 144–586 nm) on cucumbers (Cucumis sativus L.) cultivated in sandy-clay-loam field soil and compares these with the phytotoxic effects of readily soluble metal salts (Zn2+, Cu2+, and Al3+). Data revealed the cell-to-cell translocations of NPs, their attachments to outer and inner cell surfaces, nuclear membranes, and vacuoles, and their upward movements to aerial parts. Metal bioaccumulations in cucumbers were found in the order: (i) ZnO-NPs > ZnO-BPs > Zn2+, (ii) CuO-NPs > CuO-BPs > Cu2+, (iii) Al3+> Al2O3-NPs > Al2O3-BPs and (iv) TiO2-NPs > TiO2-BPs. Aging of NPs in soil for 45 days significantly enhanced metal uptake (P ≤ 0.05), for instance aged ZnO-NPs at 1 g kg−1 increased the uptake by 20.7 % over non-aged ZnO-NPs. Metal uptakes inhibited root (RDW) and shoot (SDW) dry weight accumulations. For Cu species, maximum negative impact (%) was exhibited by Cu2+ (RDW:SDW = 94:65) followed by CuO-NPs (RDW:SDW = 78:34) and CuO-BPs (RDW:SDW = 27:22). Aging of NPs/BPs at 1–4 g kg−1 further enhanced the toxic impact of tested materials on biomass accumulations and chlorophyll formation. NPs also induced membrane damage of root tissues and enhanced levels of antioxidant enzymes. The results of this study suggest that care is required when aged metal-oxide NPs of both essential (Zn and Cu) and non-essential (Al and Ti) metals interact with cucumber plants, especially, when they are used for agricultural purposes.

Expanding applications of metal-based nanoparticles (NPs) in industry and agriculture have influenced agro-ecosystems. However, relatively little is known about the bioaccumulation, distribution, and phytotoxicity of ZnO-NPs, CuO-NPs, ZnO-bulk, CuO-bulk, Zn2+, or Cu2+ in maize. Plants were exposed to 0.05-2 mg ml-1 or g-1 of six tested materials in agar (7 days) in hydroponic medium (20 days), or sandy-clay-loam soil (20 or 40 days). Seed germination, emergence and lengths of plumules, principal and seminal roots were significantly inhibited by ZnO-NPs, CuO-NPs, Zn2+, and Cu2+. Toxicity was more pronounced in hydroponic culture than in soil, and perceptible alterations in biomolecules were evident. ICP-MS analysis exhibited progressive uptake of metals while morphological, elemental, and surface/deeper scanning showed translocation and distribution of NPs in tissues. Tested materials induced enhanced superoxide radical production, lipid peroxidation, and antioxidant enzymes and proline levels. Exposure significantly reduced P-accumulation, photosynthesis, and protein production. Zn2+ and Cu2+ were found to be more toxic than NPs. Compared to 20 days exposure in soil, toxicity slightly increased after 40 days. ZnO-NPs and CuO-NPs increased apoptotic sub-G1 population by 22.4% and 38%, respectively. These results provide a better understanding of the mechanistic aspects responsible for the nanotoxicities of ZnO- and CuO-NPs in maize.

Glucose encapsulated cadmium oxide nanoparticles (G-CdO NPs) were synthesized by a sol-gel method. An array of different physical methods was used to characterize G-CdO NPs, including ultra violet-visible spectroscopy (λMax - 275 nm), transmission electron microscopy (TEM; 17 ± 1 nm), and zeta potential (−8.24 ± 0.4 mV) analyses. The NPs were active against HeLa cells (IC50 - 31.58 μg/mL) and Saos-2 cells (IC50 - 12.51 μg/mL) by preventing glycation (early, 95%; late, 65%). G-CdO NPs were effective anti-glycating agents and were highly effective against advanced glycation end products in particular. Localization of G-CdO NPs in the mitochondria and nuclei of cells was confirmed by TEM. Reactive oxygen species generated in the treated cells (confirmed by 2′,7′-dichlorofluorescin diacetate based assay) caused disintegration of mitochondrial cristae, disruption of the membrane integrity, and condensation and degradation of the nuclei. The LD50 of G-CdO NPs on Swiss Albino mice was 1.432 mg/kg of body weight. The results indicate the potential therapeutic value of G-CdO NPs.